Ciscoe Morris, Seattle Times garden writer, offers tips on planting a Japanese maple; keeping perennials blooming longer and saving a browning Alberta spruce.

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Q: Is it all right to plant a Japanese maple at this time of year? If so, are there any special requirements?

A: As long as you are able to provide adequate water, there’s no problem planting anything that comes in a pot, even trees, at this time of year. If you have a sunny spot in mind, choose carefully. Some varieties thrive in full-sun, but others require shade or at least protection from hot afternoon sunshine. Well-drained soil is also a must.

If you have clay soil or glacial till, bring in quality soil so you can plant the tree on top of a berm or in a raised bed. As long as two-thirds of the roots are above the heavy soil, the tree should thrive.

When you plant the tree, dig a hole at least twice as wide as the root ball and work in a handful of bone meal and a cup of a balanced organic fertilizer. Plant the tree at the exact same depth as it was planted in the pot.

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Last but not least, choose a Japanese maple that won’t grow too large for its location. Trees always grow at least a third bigger than it says on the tag, and it can be backbreaking and heartbreaking to remove your beautiful tree because it grew too big.

Q: Some of my summer-blooming perennials have stopped blooming. What can I do to get them flowering again?

A: It depends on which summer-blooming perennials you’re talking about. Some, such as Crocosmia, Monarda (bee balm), Astilbe and Hostas bloom only once per season, and there’s nothing you can do to get them to bloom again.

On the other hand, the foliage of some perennials such as hardy geraniums and Tradescantia (spiderwort), fall apart after blooming. Cut these plants to the ground, feed and water regularly and they will soon grow back and bloom again.

Many types of summer-blooming perennials need only to be deadheaded to encourage renewed flowering. Cut the stems of Astrantia, Agastache (hummingbird hyssop), Phygelius (cape fuchsia) and evergreen Penstemon to side buds immediately below spent flowers to encourage a second flush of blossoms to occur.

Somewhat confusing are the perennials such as Kniphofia (torch lily) and Hemerocallis (day lily). Some varieties repeatedly flower while others only bloom once per season. Usually the plant tag will tell you, but if you don’t know which kind you have, there’s only one way to find out. Feed, water, deadhead and keep your fingers crossed. If it’s a repeat bloomer, flower stalks should emerge from the base in a matter of days.

Q: My Alberta spruce is turning brown. Can I save it?

A: Typically when the foliage on Alberta spruce turns brown in summer, it’s caused by spider mites. These practically microscopic critters suck the juice out of the needles. They also attack other types of spruce and sometimes cause similar damage to arborvitae.

Spider mites are usually present in small numbers year round, but it’s in hot, dry weather when they build up to damaging populations.

While mites rarely kill a tree, it’s important to take steps to solve the problem before severe infestation occurs; otherwise, you’ll be left with a bare and ugly tree until new growth fills in the following spring.

An effective environmentally friendly way to control spider mites is to use your hose nozzle to blast the interior of the tree with powerful sprays of water. This not only knocks the mites off the leaves, but also adds humidity, which greatly slows reproduction in mites. Blasting away everyday for a couple of weeks almost always solves the problem and blows the dead leaves off in the process.

Next summer, start your water sprays as soon as hot weather begins. As long as the tree is otherwise healthy, your tree should remain green and attractive all season long.

Ciscoe Morris:; “Gardening with Ciscoe” airs at 10 a.m. Saturdays on KING-TV.

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